As the Reddit hoard has pointed out, this dude, “Big Joe” was probably not actually the largest man in the world but rather just billed that way for a circus sideshow. Also, he may have been very tall, which changes perspective a bit.
BUT the point remains that people in 1903 PAID MONEY TO SEE a guy who looks… well, like guys everywhere in America now. Even, as pointed out above, a random cop. That is shocking on some level, and an important reminder that overweight people are not born with fat genes but rather living a fat lifestyle. And that they can change.
You’re not fat because of your genes—well, unless maybe you’re a true outlier like Big Joe—you’re fat because you eat too much and exercise too little.